Comments 4

If You get sensors from Arduino it will be easier to add the code, there are many sample codes for each sensor.
Make sure your PHP website has fopen (file open) enabled. Add the php script to the page on your website.

This project is based on the idea of using your website as a cloud. In this setup the ESP is a wifi station and it doesn't listen to requests, it transmits data to the website every period of time set by the Arduino. It means that in your browser you can see the recently sent data. It can be like real time data if you transmit the data every few seconds.
The better way is setting up the ESP as a server that listens continuously for requests and reply to them. For that it requires complex code that can understand the request and compose a reply. You also need to setup the Port Forwarding in your router.